Goldacre is known in particular for his Bad Science column in The Guardian, which he wrote between 2003 and 2011, and is the author of three books: Bad Science (2008), a critique of irrationality and certain forms of alternative medicine; Bad Pharma (2012), an examination of the pharmaceutical industry, its publishing and marketing practices, and its relationship with the medical profession,[9] and I Think You'll Find It's a Bit More Complicated Than That,[10] a collection of his journalism. Goldacre frequently delivers free talks about bad science—he describes himself as a "nerd evangelist."[11][12]

In 2015, Goldacre moved to the Nuffield Department of Primary Care Health Sciences's Centre for Evidence-Based Medicine, joining a project funded by a grant from the Laura and John Arnold Foundation.[29]

Goldacre is known for his weekly column, "Bad Science," in the Saturday edition of The Guardian, which he started in 2003 [37] and wrote until November 2011.[38] Devoted to criticism of scientific inaccuracy, health scares and pseudoscience, the column focuses on the media, marketing, problems with the pharmaceutical industry, and its relationship with medical journals and alternative-medicine practitioners.[39][40][41]

While investigating McKeith's membership of the American Association of Nutritional Consultants, Goldacre purchased a "certified professional membership" on behalf of his late cat, Henrietta, from the same institution for $60.[49]

In February 2007 McKeith agreed to stop using the title "Doctor" in her advertising, following a complaint to the Advertising Standards Authority by a "Bad Science" reader.[50] In an interview with Richard Saunders of the podcast Skeptic Zone, Goldacre said, "Nutritionists are particularly toxic because they are the alternative therapists who, more than any other, misrepresent themselves as being men and women of science."[51]

In 2008, Matthias Rath, a vitamin entrepreneur, sued Goldacre and The Guardian over three articles,[52][53][54] in which Goldacre criticised Rath's promotion of vitamin pills to AIDS sufferers in South African townships.[55] Rath dropped his action in September 2008 and was ordered to pay initial costs of £220,000 to The Guardian.[55] The paper is seeking full costs of £500,000, and Goldacre has expressed an interest in writing a book about Rath and South Africa, as a chapter on the subject had to be cut from his book while the litigation proceeded.[56] The chapter was reinstated in a later edition of the book, and also published online.[57] Goldacre continues to cite Rath as a proponent of harmful pseudoscience.[58]

Goldacre's first book, Bad Science, was published by Fourth Estate in September 2008.[59] The book contains extended and revised versions of many of his Guardian columns. It was positively reviewed by the British Medical Journal (BMJ) and The Daily Telegraph, and reached the Top 10 bestseller list for Amazon Books.[60] It was nominated for the 2009 Samuel Johnson Prize.[61][62] In an interview in 2008, Goldacre said that "one of the central themes of my book [Bad Science] is that there are no real differences between the $600 billion pharmaceutical industry and the $50 billion food supplement pill industry."[63]

His second book, Bad Pharma: How Drug Companies Mislead Doctors and Harm Patients, was published in the UK in September 2012 and in the United States and Canada in February 2013.[64] In the book he argues that:

Drugs are tested by the people who manufacture them, in poorly designed trials, on hopelessly small numbers of weird, unrepresentative patients, and analysed using techniques which are flawed by design, in such a way that they exaggerate the benefits of treatments. Unsurprisingly, these trials tend to produce results that favour the manufacturer. When trials throw up results that companies don't like, they are perfectly entitled to hide them from doctors and patients, so we only ever see a distorted picture of any drug's true effects. Regulators see most of the trial data, but only from early on in a drug's life, and even then they don't give this data to doctors or patients, or even to other parts of government. This distorted evidence is then communicated and applied in a distorted fashion. In their forty years of practice after leaving medical school, doctors hear about what works through ad hoc oral traditions, from sales reps, colleagues or journals. But those colleagues can be in the pay of drug companies – often undisclosed – and the journals are too. And so are the patient groups. And finally, academic papers, which everyone thinks of as objective, are often covertly planned and written by people who work directly for the companies, without disclosure.[65]

The Committee for Skeptical Inquiry (CSICOP) presented in 2006 the Balles Prize in Critical Thinking award for his column in The Guardian U.K. newspaper, Bad Science Columns include "Dyslexia 'cure' fails to pass the tests", "Bring me a God helmet, and bring it now", "Kick the habit with wacky wave energy", "Brain Gym exercises do pupils no favors" and "Magnetic attraction? Shhhh. It's a secret"[81]

^Saunders, Richard. "The Skeptic Zone #16 – 06.Feb.2009". The Skeptic Zone. Retrieved 2014-05-14. There are bad things happening in medicine and academia but people talk about them, people criticize them, you know, and in the world of alternative therapies, you can be as far out as Matthias Rath and nobody will say a word.